This is a phase I-II trial of ingested interferon-alpha (IFN-a) in insulin dependent diabetes mellitus (IDDM), an autoimmune disease. It will study the effect of IFN-a on immune function and Beta cell function and destruction in IDDM. Subjects with newly diagnosed IDDM will be enrolled for a treatment period of up to 12 months. Establishment of clinical improvement or immunosuppression with ingested IFN-a may lead to a placebo-controlled phase II-III trial with persistent improvement in clinical disease as a primary outcome.